In the Star Trek Discovery Episode S1:E9 Into The Forest I Go, Saru tells Captain Lorca:

I have no idea where we are.

Today we have GPS navigation systems and sonar, but naval navigators of today have a passing understanding of our constellations, and can at least use them to orient themselves.

We know that in Star Trek their movements are generally limited to our Galaxy. In the 23rd Century (as today), all the stars in our Galaxy would have a distinctive signature.

It seems reasonable that Saru could look up the signatures of all the visible stars on his database, and from that triangulate his position.

The only extra piece of information we have is that Captain Lorca entered the coordinates before the Spore drive jump.

My question is: In Star Trek Discovery why can't Saru triangulate their position from the stars?

Edit: there was a request for detail on the triangulation method. Agree that spectrospcopy is insufficient, and pulsars are a slight possibility, but the positions of other galaxies seems to be the way to do it.

  • You wouldn't use all stars, you'd use pulsars to triangulate. That's the method used on the Voyager plaques to identify the location of Sol. – Keith Morrison Dec 4 '17 at 19:38
  • All the visible stars? Nope. – Martin Schröder Dec 4 '17 at 22:58
  • 3
    I'm voting to close this question as off-topic because of our Future Works policy. – user931 Dec 13 '17 at 8:17
  • Hi @Bat - I’m unfamiliar with the future world policy. Could you please provide a link or reference? – hawkeye Dec 13 '17 at 10:56

Space is transparent. Very, very, very transparent. Even nebulas are very, very, very transparent. Nebulas only look opaque in astronomical photos because long exposures are used to gather light over hours to make them look thousands of times brighter and more visible than they are.

Thus all the opaque nebulas in Star Trek must be very, very, very tiny sections of nebulas, tiny sections with densities millions, and billions, and trillions of times greater than the typical densities of those nebulas. No doubt astronomers have never detected those tiny super dense sections of nebulas seen in Star Trek because they are so extremely tiny compared to the nebulas they are in.

So almost every where in our galaxy there is a clear view in almost every direction for millions and billions of light years. Humans have stereoscopic vision, being able to see nearby objects with two separate eyes a couple of inches apart and thus see how far away they are. If human eyes were two feet apart our stereoscopic vision could see the distances of objects 12 times farther away; if human eyes were two miles apart our stereoscopic vision could see the distances of objects 63,360 times farther away.

The principal of stereoscopic vision is the same as the principal of parallax used to measure how far away stars are. The angle to a star is measured with fantastic precision at different times 6 months apart, when the Earth is 180,000,000 miles apart on its orbit. The very tiny difference in the angles to the star gives the parallax and thus the distance to the star. Parallax can be measured accurately out to distances of several hundred light years.

If a spaceship travels to two places 18,000,000,000 miles apart it should be able to use 2017 era telescopes to measure the distances to objects hundreds of thousands of light years away as accurately as 2017 astronomers measure the distances of stars hundreds of light years away.

If a spaceship travels to two places 18,000,000,000,000 miles apart it should be able to use 2017 era telescopes to measure the distances to objects hundreds of millions of light years away as accurately as 2017 astronomers measure the distances of stars hundreds of light years away.

18,000,000,000,000 miles is about three light years. The nearest star system to Earth's solar system is Alpha Centauri at a distance of about 4.3 light years. By the time of Discovery Starfleet has visited many stars that are tens and hundreds of light years from Earth, perhaps some that are thousands of light years from Earth.

In most regions of space, especially in interstellar space outside a solar system and light years from the nearest stars, some of the brightest objects will be ordinary stars that happen to be very close but many of the brightest objects will be objects that are far away and intrinsically very bright.

So the way for a starship to find out where it is to search all around in 360 degrees for the brightest objects in various frequencies of the electromagnetic spectrum. Unless the starship is in a solar system only millions or billions of miles from a star, the brightest X ray object detected should be the great galaxy M87 millions of light years away, for example. So comparing the spectrum of the brightest X ray source should show that it is M87 and the angle between M87 and, for example, the center of our galaxy should help orient the starship and give an idea of what galactic region it is in.

And if the brightest X ray source is not a star only millions or billions of miles away, or the galaxy M87, it must be a star or other object that is only the brightest X ray source within a relatively small region of space near it. If the X ray source's spectrum identifies it as a known X ray source with a known position and known absolute brightness, its apparent brightness will show how far away the starship is from that X ray source.

Doing that with about 10 frequencies should establish the starship's exact location. Not having seen "into the Forest I Go" I can only guess that Saru is doing that but hasn't completed it yet when he tells the captain he doesn't know where they are. If the Spore Drive instantly jumps a ship from one place to another, starships that use it should be equipped with automatic telescope and computer navigation systems to swiftly measure the ship's new position.

Apparently the possibility of equipping starships with the Spore Drive caused Starfleet to upgrade the navigational systems of starships to swiftly update the position of a starship by the first season of TOS a few years later.

In "Arena" the Metrons transport the Enterprise away from their star system:

(Kirk suddenly appears in front of the crew, who all leap to their feet.)

UHURA: Captain! Are you all right?

KIRK: I don't know. I don't know. All right, everybody. Back to your posts. Let's get out of here.

(He takes his seat.)

SULU: Captain.

KIRK: Mister Sulu.

SULU: It's impossible, but there's Sirius over there when it should be here. And Canopus. And Arcanis. We're. All of a sudden, we're clear across the galaxy, five hundred parsecs from where we are I mean, were. I mean

KIRK: Don't try and figure it out, Mister Sulu. Just plot a course for us back to Cestus Three.


  • If I remember correctly, somewhere in the later expanded universe material it's explained that galactic locations are triangulated by identifying Cepheid variables, which are about 800 (currently known) bright, giant regularly pulsating stars across the Milky Way. If the Cepheids you can detect (which should be fairly trivial even with early Federation tech) don't match part of that pattern, you're not in our galaxy. – jeffronicus Dec 4 '17 at 17:09

We know that in Star Trek their movements are generally limited to our Galaxy.

This assumption is wrong here. Spores Drive is a special case. When Mycelial Network was first introduced, Stamets called it "The veins and muscles that hold our galaxies together". Later, in the series, this network was clarified as a microscopic web spanning the entire cosmos, an intergalactic ecosystem.

Also, in the same episode S01E09 you mentioned,

Lorca: Let me show you something.

Stammets: You've been accumulating this data from my jumps the whole time? Mm-hm.

Lorca: And these scattered pockets of negative mass.

Stammets: They could indicate alternative parallel universes connected to the mycelial network.

Lorca: And with more jumps, we could find a pattern, perhaps even the coordinates to reach them.

Lorca: You showed me this invention could take us to places that we never dreamed we could reach.

Lorca: Places far beyond our preconceptions of time and space.

Stammets: Captain, I didn't know you cared.

enter image description here

As Stamets could unintentionally navigate to anywhere in the Mycelial Network, USS Discovery can end up in an alternative parallel universe, let alone another galaxy or uncharted quadrant of same galaxy.

Only future episodes will tell.

The recent episode S01E10 confirmed that my guess is correct. USS Discovery is indeed in an alternate universe. Mirror Universe to be precise.

BTW, they were also able to find their position from galactic center.

  • The marked quotes don't necessarily prove that you can spore jump to another galaxy. It is correct that you can, but your supposed proof just doesn't back that up. (1) Parallel universe jumps could possible happen "in place" (similar to how e.g. some time travel machines only travel in time but remain in the same geographical location) (2) "Far beyond" is figurative, not literal, distance. It doesn't specifically state that you can travel long distances, it simply states that you can travel spacetime in new ways that weren't yet known about. – Flater Feb 25 '19 at 11:17
  • @Flater Is there any reason to believe that star maps are same in different universes? – user931 Feb 25 '19 at 11:38
  • I'm not sure what you're responding to in my comment. I considered the same thing, as this may have been the reason why Saru's instruments were failing him. – Flater Feb 25 '19 at 11:43

As mentioned earlier in the episode:

Lorca has been able to map a route to another universe. Knowing this would be his last chance, he has plotted at route there. Due to the infinite possible differences we would certainly have a different configuration of stars. I am certain any one there will all speak English though.

  • When exactly did he do that? (must have missed the other U. part there). Even with that I have come to a similar conclusion as to WHERE they are, but I really did not notice Lorca plotting something to there on purpose? – Thomas Dec 4 '17 at 20:10

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